Publicação
Sensor based on β - NiOx hybrid film/multi-walled carbon nanotubes composite electrode for groundwater salinization inspection
| dc.contributor.author | Firmino, Mônica L.M. | |
| dc.contributor.author | Morais, Simone | |
| dc.contributor.author | Correia, Adriana N. | |
| dc.contributor.author | Lima-Neto, Pedro de | |
| dc.contributor.author | Carvalho, Francisco A.O. | |
| dc.contributor.author | Castro, Suely S.L. | |
| dc.contributor.author | Oliveira, Thiago M.B.F. | |
| dc.date.accessioned | 2019-06-06T14:50:35Z | |
| dc.date.available | 2019-06-06T14:50:35Z | |
| dc.date.issued | 2017 | |
| dc.description.abstract | The enrichment of groundwater with different nutrients (Na+, Ca2+, Mg2+, Cl−, CO32−, among others) triggers the salinization of the aquifer and makes it inappropriate for many purposes. In this work, we developed a highly sensitive and selective electrochemical sensor, based on Ni-inorganic films electrosynthetized in situ onto multi-walled carbon nanotubes composite paste electrode (MWCNE), which allows the early detection of salinization. The working sensor (β-NiOx/MWCNE) was derivatized from nickel hexacyanoferrate modified electrode in strong alkaline medium (pH = 12), producing a hybrid film composed by β-Ni(OH)2 and β-NiO(OH). The electrochemical properties, morphology and chemical composition of the formed β-NiOx thin films were evaluated by voltammetry, scanning electron microscopy and X-ray spectroscopy. The developed β-NiOx/MWCNE sensor was highly sensitive to the presence of Na+ cation by ion-exchange, and the increase of Na+ concentration in the range 4.46 × 10−7 to 4.93 × 10−6 mol L−1 inhibited linearly the reversible electrochemical signal of the device, allowing to determine trace concentrations of this ion (LOD = 9.86 × 10−8 mol L−1) with high correlation coefficient of the data (r = 0.999) and suitable precision/reproducibility of the measurements (RSD < 9%). Using Na+ as salinization marker and β-NiOx/MWCNE as electroanalytical device, we found evidences of groundwater salinization in Grossos, a Brazil coast city, whose inhabitants have hypertension above the national average. The attained results were comparable to those obtained by the standard methods for Na+ analysis (percentage error ranging from 0.5 to 1.6%), confirming the accuracy of the proposed electroanalytical platform. | pt_PT |
| dc.description.version | info:eu-repo/semantics/publishedVersion | pt_PT |
| dc.identifier.doi | 10.1016/j.cej.2017.04.077 | pt_PT |
| dc.identifier.issn | 1385-8947 | |
| dc.identifier.uri | http://hdl.handle.net/10400.22/13896 | |
| dc.language.iso | eng | pt_PT |
| dc.peerreviewed | yes | pt_PT |
| dc.publisher | Elsevier | pt_PT |
| dc.relation.publisherversion | https://www.sciencedirect.com/science/article/pii/S1385894717306204?via%3Dihub | pt_PT |
| dc.subject | Groundwater salinization | pt_PT |
| dc.subject | Sodium cation | pt_PT |
| dc.subject | Nickel thin films | pt_PT |
| dc.subject | Ion-exchange | pt_PT |
| dc.subject | Electrochemical sensor | pt_PT |
| dc.title | Sensor based on β - NiOx hybrid film/multi-walled carbon nanotubes composite electrode for groundwater salinization inspection | pt_PT |
| dc.type | journal article | |
| dspace.entity.type | Publication | |
| oaire.citation.endPage | 55 | pt_PT |
| oaire.citation.startPage | 47 | pt_PT |
| oaire.citation.title | Chemical Engineering Journal | pt_PT |
| oaire.citation.volume | 323 | pt_PT |
| person.familyName | Morais | |
| person.givenName | Simone | |
| person.identifier | 1598822 | |
| person.identifier.ciencia-id | B111-BBFB-F200 | |
| person.identifier.orcid | 0000-0001-6433-5801 | |
| person.identifier.scopus-author-id | 7007053747 | |
| rcaap.rights | openAccess | pt_PT |
| rcaap.type | article | pt_PT |
| relation.isAuthorOfPublication | 7a9c7d63-a6c7-4159-b12d-b049b8c5c8f9 | |
| relation.isAuthorOfPublication.latestForDiscovery | 7a9c7d63-a6c7-4159-b12d-b049b8c5c8f9 |